Lengthening metallic beams



(No Model.) v

' P. H. JACKSON.

LENGTHENING METALLIC BEAMS.

No. 444,578. Patented Jan. 13, 1891 we wows ve'rsns 0a., mam-mam,wl-snmcvcn, n. c.

UNITED STATES PATENT OFFICE.

PETER H. JACKSON, OF SAN FRANCISCO, CALIFORNIA.

LENGTHENING METALLIC BEAMS.

SPECIFICATION forming part of Letters Patent No. 444,578, dated January13, 1891.

Application filed March 19, 1890.

To all whom it may concern.-

Be itknown that I, PETER H. JACKSON, a citizen of the United States,residing in the city and county of San Francisco, State of California,have invented an Improvement in Lengthening Metallic Beams; and I herebydeclare the following to bea full, clear, and exact description of thesame.

My invention relates to a means for lengthening iron and steel rolledand other metal beams and strengthening the joint; and it consists in ameans for uniting the abutting ends of such beams in such a manner as toincrease the strength of the beam thus united at its point of union. 7

Referring to the accompanying drawings for a more complete explanationof my invention, Figure 1 is a side elevation showing one form of union.Fig. 2 is a transverse section of the same. Fig. 3 is a View showingcheekpieces used with this coupling.

The capacity of rolling-mills limits the length of rolled beams, andwhen beams are needed of greater length to span large rooms or otherspaces, either a supporting column, pier, or post must be used, or ifsuch support be inadmissible it is necessary to build up what is knownas a plate or box girder at an increased cost over'the rolled beams andwith a less reliable strength on account of its being built of a numberof pieces and riveted together.

It is important when a number of beams or girders of great length areemployed that there should be as little deflection as possible, andmyimproved construction is designed to increase the strength of thegirder at the point where the joint is made. 111 the first method ofconstruction which I have shown I employ cheek-pieces A, which are madeof iron or steel, the latter being preferred. These pieces are ofsufficient length to extend some distance on each side of the abuttingends of the beams B, and they inclose the beams upon each side of theirabutting ends, extending upon each side of the web and inclosing the topand bottom flanges of the beam, as shown,

The plates D extend along the top and bot tom, projecting on each sideso that their edges are flush with the flanges C of the Serial No.344,557. (No mo el.)

beams. The cheek-pieces A are secured to the webs B and also to theflanges C of the beams by a sufflcient number of rivets, and the top andbottom plates D are secured to the cheek-pieces and also through the topand bottom flanges of the beams in a similar manner by rivets, so thatthe whole is solidly secured together. The cheek-pieces practically formexternal girders having a similar shape to the girder or beam which theyinclose, and being secured thereto with the top and bottom plates theyform an inclosing boX, within which the ends of the beams meet and bywhich they are held with a strength which is even greater than any otherportion of the beam and in excess of all requirements for the strain towhich the beam will be subjected. The top and bottom flanges of these ceek-pieces may be made thicker in the middle than at the ends, the swellor taper giving additional strength at the joint or meeting point ofabutting beams, as shown at a.

In some casesit may be desirable to extend the top and bottom platesbeyond the beam flanges, and employ tie-bolts E, which pass throughthese plates, being secured by nuts screwed upon the ends of the bolts,and blocking-pieces F may be fitted into the concavity or depressionformed in the sides of the cheekpieces, so as to fill up these spacesflush with the outer edges of the top and bottom plates. Theseblocking-pieces may be secured in place by bolts passing transverselythrough them or may be recessed for the vertical bolts E, thecheek-pieces, and the webs of the abutting beams with the top and bottomflanges, thus providing sufficient strength to resist all tensile,compressive, and shearing strains which may occur. s

In place of the bolts or rivets which are used to secure thecheek-pieces, plates, and blocking-pieces, it will be manifest that thecontinuous bands K may be employed to hold these parts in place as shownin Fig. 4.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

l. A means for lengthening metallic beams, consisting of metallicinclosing plates or cheek-pieces extending across the point of meetingof two abutting beams and fitting the webs and heads of said beams, incombination with top and bottom plates extending over said heads andsaid cheek-pieces, and the top and bottom plates being riveted togetherand to the heads of the inclosed beams, substantially as hereindescribed.

2. The improvement in lengthening rolled beams and strengthening thejoints formed by the meeting ends of two beams, consisting of metalcheek-pieces fitting the webs and heads of the beams, top and bottomplates riveted to said cheek-pieces and to the heads, and rivets passingthrough the cheek-pieces and the webs of the beams, substantially asherein described. 15

In witness whereof I have hereunto set my hand.

PETER H. JACKSON.

Witnesses:

GEO. H. STRONG, S. II. NOURSE.

